Measurements of ttcross sections in association with b jets and inclusive jets and their ratio using dilepton final states in pp collisions at √s = 13 TeV
The cross sections for the production of ttbb and ttjj events and their ratio σ_(ttbb)/_(ttjj) are measured using data corresponding to an integrated luminosity of 2.3 fb^(−1) collected in pp collisions at √s = 13 TeV with the CMS detector at the LHC. Events with two leptons (e or μ) and at least four reconstructed jets, including at least two identified as b quark jets, in the final state are selected. In the full phase space, the measured ratio is 0.022 ± 0.003(stat) ± 0.006(syst), the cross section σ_(ttbb) is 4.0 ± 0.6(stat) ± 1.3(syst)pb and σ_(ttjj) is 184 ± 6(stat) ± 33(syst)pb. The measurements are compared with the standard model expectations obtained from a powheg simulation at next-to-leading-order interfaced with pythia
